As a British disgustologist visiting the USA this month, I was struck by all the Halloween decorations. Why did almost every porch sprout pumpkin skulls, gravestones, body parts, bloody cleavers, witches, zombies, spiders and ghouls? Why so many Halloween party shops and shelves of disgusting worm-shaped candy? And, for that matter, why—Halloween notwithstanding—do Brits, Americans and other nations alike, seek to entertain themselves with the nasty, the scary, the gory and the repulsive? What’s the attraction of an Alien bursting from a gut or an explosion of bloody bodies in a Tarantino climax? Why did Grand Theft Auto, which lets players kill with baseball bats and cannibalise corpses, gross a billion dollars in three days?
Halloween has a long cultural history, as a festival of the dead, as ritual to placate marauding spirits, as a harvest celebration and as a chance for kids to party. But, as with most cultural phenomena, it is underpinned by a number of basic human emotions. So let’s untangle the motives that are at play here.
First of all fear. Halloween is Fright Night, when the ghosts of the dead are supposed to scare us and when we watch thrillers about axe murderers. Although we learn what specific things to fear, fear is a part of human nature. And, of course, we are not the only species to be fearful. This is a motive with a simple job to do, to keep animals from being eaten by other animals. When an ant flees an anteater, when a chaffinch freezes in the presence of a sparrowhawk, or when a gazelle flees a hyena, their fear system is engaged. The system focuses attentional resources on the danger and it motivates evasive action. Without such systems all prey species would have been eaten and would now be extinct. Humans are no exception; it’s a fair bet that you are descended from a long line of fearful people. Ancestral voices tell us to beware; to freeze or flee in the presence of dangers. So why do we fear fantastical monsters, ghosts and zombies? Powerful emotions create powerful associations. The grass shivers—is it a snake? A twig snaps—is it the next door tribe on a raid? That strange-acting local woman—did she use witchcraft to kill my brother? And is that eerie whisp of smoke the evil spirit that carried off my infant?